There has been some debate among guitar players about which one is better than the other. If somebody would ask me I would select DiMarzio personally for reasons that it has more character than Seymour Duncan.
I based my review on this subject by experience. After a long time installing guitar pickups to a lot of guitars, I found DiMarzio got more character to its sound. However, if a customer wants to have a sound like his favorite artist and that artist is using a Seymour Duncan for sure I would advise him or her to get a Seymour Duncan pickup the same model used by the artist if possible. Seymour Duncan is very good with tone shaping.
Then why do I still like the DiMarzio? Well, it interacts well with whatever coil combination you have on your guitar. (Ex. Full Humbucker, Parallel Humbucker, Single Coil North, Single Coil South, In Phase, Out of Phase).
If you are a gigging musician, you don’t want to sound like one artist and sound crap covering another artist. You should have flexibility on your guitar so you can sound decent enough compared to the original sound.That is the purpose of split coil combinations.
The most popular of the pickups I have installed is the DiMarzio CrunchLab on the bridge position and DiMarzio LiquiFire in the neck position. This has been the signature of John Petrucci of Dream Theater for a very long time before he switched to his Illuminator pickups.
All my customers love this as an all around pickup. Again I would like to emphasize that an all-rounder pick up is essential for a gigging guitarist. It got a decent output, so it will not sound tiny when split into a single coil. The combination is also cheaper than a comparable Seymour Duncan.
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